Video report by ITV's Good Morning Britain
Girls Aloud singer Nicola Roberts says a new cancer research project in memory of Sarah Harding will help "carry on her legacy".
Harding, who was part of the pop group Girls Aloud, died from breast cancer aged 39 in 2021.
One of her final wishes was to find new ways of spotting the disease early, when it is more treatable.
The new Breast Cancer Risk Assessment in Young Women (Bcan-Ray) project is one of the first in the world to identify which women are at risk of getting the disease in their 30s.
Speaking about the loss of Sarah, Girls Aloud bandmate Nicola Roberts told Good Morning Britain: "Everybody deals with grief in different ways.
"Some people deal with it head on. For me, it's still not really that real.
"A lot of the time I'm like 'she's in Thailand on the beach' or she's in Ibiza with her friends. Then I'm reminded that she's not.
"Her wish was to participate in all the fundraising we've been doing.
"She was always so authentic. For her to carry that legacy on and we can take the baton for her and help the women who grew up with the band.
"It's so important for her and it's important for us."
Around 2,300 women aged 39 and under are diagnosed with breast cancer in the UK each year.
Caroline Padmore, 33, from Stockport is one of the first to take part and is having a mammogram at Wythenshawe Hospital.
Caroline said: "The more that we know especially for women at this age, the more we can look at ways to diagnose and treat earlier to not as many women need to go through what Sarah went through."
There is currently no routine screening programme for early breast cancer in younger women who don’t have family history of the disease, despite it being the most common cause of death in women aged 30-55 years.
The project will determine risk factors most commonly found in women diagnosed with breast cancer in their early 30s, they will build a model with this data which will in turn help to enable all women to have a risk assessment for breast cancer when they reach the age of 30.
Those women identified as high risk could then have access to early screening and opportunities for prevention, to reduce the chances of them developing and potentially dying from the disease.
Speaking about the importance of cancer research before her death, Sarah said: “Research is incredibly important in the fight against cancer.
"Although this research may not be in time to help me, this project is incredibly close to my heart as it may help women like me in the future.”
There are currently around 80 women in their 30s who have taken part in the study. They are hoping to recruit up to 750 women.
The study looks at the density of breast tissue by taking a low dose mammogram - the mammogram doesn't identify cancer but does look at the make up of the breast tissue
This then can provide a risk assessment for the women taking part if they are of increased risk of breast cancer.
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